Determining the Influence of Surface Winds on the Behavior of Aquatic Invertebrates

Abstract:

Climate change is expected to alter meteorological statistics and patterns across the world, with many areas projected for increased mean and extreme temperatures and precipitation. As this transition alters global atmospheric patterns, it is expected that average surface wind speeds will change as well, with specific projections varying by region or time of year. However, the extent that more intense or frequent surface winds may impact aquatic ecosystems is largely undescribed compared to other meteorological phenomena. The objective of this study was twofold: 1) determine how surface wind speeds influence the behavior of individual aquatic invertebrates, and 2) determine how surface wind speeds influence interactions between predator and prey species. Backswimmers (Notonectidae), water boatmen (Corixidae), and dragonfly nymphs (Anisoptera), were collected from ponds across Penn State Behrend’s campus. For individual behavioral assessment, one subject was placed into a partitioned 10-gallon tank and exposed to surface wind treatments generated by a fan. Wind speeds ranged from 0 to 5.2 m/s and were randomly adjusted in five-minute intervals, for a total of 30 minutes. To assess predator-prey interactions, a dragonfly nymph and a backswimmer or water boatman were both placed into the same portion of the tank, and the same treatments were applied. Noldus EthoVision XT software was used to record each trial and quantify individual space use (i.e., time spent in certain portions of the tank), as well as movement frequency and velocity. The data from these trials are currently undergoing analysis and will be discussed further at the Sigma Xi Undergraduate Research Conference. It is anticipated that these findings can provide insight into how greatly aquatic ecosystems may be impacted by changes in surface wind speeds. Drastic changes in trophic interactions or movement patterns due to surface winds could potentially transform population abundance or distribution in ecosystems across the world.